Claims
- 1. A method of removing a contaminant comprising at least one of arsenic and selenium from a synthetic hydrocarbonaceous fluid containing same comprising
- a. preparing a guard bed having a plurality of sections; at least one section which is to be contacted by said fluid and contaminant first having from about 10 to about 75 percent by volume occupied by a contaminant-removing material composed of a carrier material carrying active material, the remainder being essentially an inert material different from said contaminant-removing material; said contaminant-removing material being particulate and consisting essentially of a material selected from the group consisting of iron, cobalt, nickel, at least one oxide thereof, at least one sulfide thereof, and combinations of two or more thereof; said inert material being stable at temperatures in excess of 850.degree. F and inoperable to remove said contaminant from said fluid; said guard bed having a least one additional section having its volume substantially completely occupied by said contaminant-removing material for additional removal of contaminant from said hydrocarbonaceous fluid;
- b. flowing said hydrocarbonaceous fluid through said first section of said guard bed under a reducing atmosphere, in the substantial absence of water, and an elevated temperature of from about 300.degree. to about 550.degree. F to effect a reduction in the concentration of said contaminant in said hydrocarbonaceous fluid and deposition of said contaminant in said first section of said guard bed; and, thereafter,
- c. flowing the hydrocarbonaceous fluid reduced in said contaminant into contact with said at least one additional section of said guard bed under essentially the same conditions as step b. above except that the temperature in said at least one additional section is higher than the temperature in said first section and from about 550.degree. to about 850.degree. F to effect a further reduction of the concentration of said contaminant.
- 2. The method of claim 1 wherein said contaminant-removing material comprises a plurality of particles of a carrier material selected from the group consisting of silica, alumina, magnesia, zirconia, thoria, zinc oxide, chromium oxide, clay, Keiselguhr, Fuller's earth, pumice, bauxite and combinations of two or more thereof; said carrier material carrying an active material as defined in claim 1; said carrier material having a pore volume of at least 0.8 cubic centimeters per gram and a surface area in excess of 100 square meters per gram and having feeder pores having radii greater than 1,000 angstroms disposed therethrough for allowing said hydrocarbonaceous fluid and said contaminant to contact substantially all of said active material; said active material being disposed at least adjacent said pores.
- 3. The method of claim 2 wherein said carrier material is alumina and said active material is selected from the group consisting of an oxide of iron, a sulfide of iron, and combinations thereof.
- 4. The method of claim 2 wherein said guard bed includes at least one terminal section that has substantially all of its volume occupied by said contaminant-removing material.
- 5. The method of claim 1, wherein said guard bed includes more than two sections; at least one of said sections being a terminal section that is disposed at the downstream end of said bed so as to be the last section to be contacted by said hydrocarbonaceous fluid; said terminal section includes a plurality of particles of hydrogenation catalyst for substantially complete removal of said contaminant from said hydrocarbonaceous fluid.
- 6. The method of claim 5 wherein at least one of said terminal sections has substantially all of its volume occupied by said contaminant-removing material.
Cross References to Related Applications
This is a continuation-in-part of U.S. Pat. application Ser. No. 548,516, filed Feb. 10, 1975 now abandoned.
US Referenced Citations (7)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
548516 |
Feb 1975 |
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